Abstract: Image display apparatus comprising a projector, at least one primary modulator (4,6,8) for modulating light, an auxiliary modulator (36) for modulating the light modulated by the primary modulator, and an optical device (32) for relaying the light modulated by the primary modulator to the auxiliary modulator (36), the optical device (32) comprising a concave mirror and at least one refractive element.

Abstract: Image display apparatus (2) which combines low and high resolution image data in a common data format prior to display.

Abstract: A vehicle simulator comprising: (i) a real-world vehicle (1) whose controls and instruments are dual-mode such that they can be switched between normal operation and simulated operation; (ii) a retro-reflecting screen (3) which is deployed around and outside windows of a control area (cockpit) of the vehicle (1), which control area is for a person operating the simulator; (iii) an image projector (9) for being mounted on a head or headwear of the operator; (iv) a head position and orientation sensing system (11) mounted on the head or the headwear of the operator; (v) a simulator host computer that receives information from controls of the vehicle (1) and sends information to the controls and to instruments of the vehicle (1) when the vehicle (1) is in a simulation mode; and (vi) an image generator computer (8) that receives data from the simulator host computer regarding the vehicle's simulated position and orientation and that also receives data from the head position and orientation sensing system (11)

Abstract: Illumination apparatus (8) which comprises at least two light sources, at least one light collecting device for collecting light from the light sources (10), motion providing means for providing relative motion between the light sources (10) and the light collecting device (14), and control means for controlling the illumination of the light sources (10) such that the light sources (10) are illuminated for a predetermined time period when in a predetermined position relative to the light collecting device (14).

Abstract: Image display apparatus comprising projector means, optical means for splitting incident light, a first modulator for modulating red light, a second modulator for modulating green light, a third modulator for modulating blue light, optical means for recombining the combined modulated red light, green light and blue light, and control means for controlling the operation of the first, second, third and fourth modulators such that the dynamic range of the image display apparatus is enhanced.

Abstract: Collimated visual display apparatus comprising an aspheric screen (12) and a curved collimating mirror (16), characterised in that the aspheric screen (12) is not a surface of revolution about an axis, the aspheric screen (12) comprises first and second parts (6, 8) which are separated from each other by a third part (10), the first and second parts (6, 8) are curved in cross section and if connected together then they would form a surface of revolution, the third part (10) is straight in cross sectional view and is a short cylindrical centre section, and the collimated visual display apparatus is such that the aspheric screen (12) has an outer curved surface that is viewed via the curved collimating mirror (16) by a user of the collimated visual display apparatus.

Abstract: An eyepiece (2) for viewing a flat image, which eyepiece (2) has a wide field of view and which eyepiece (2) comprises a cemented doublet of reflecting and refracting optical components, the reflecting and refracting optical components being such that they are each of a different refractive index whereby chromatic aberrations and spherical aberrations are reduced.

Abstract: A method of constructing a thin film mirror, which method comprises: (i) providing a suction chamber (2) with edges (4) which lie on a required mirror surface; (ii) providing tensioning means which is forced into contact with film (8) adjacent to at least one of the edges of the suction chamber such that tension in the film parallel to the edge is increased; and (iii) providing holding means (12) for (a) holding the tensioning means (10); (b) locally adjusting holding pressure on the tensioning means (10); and (c) feeding the tensioning means (10) into position after the film (8) has been attached to the suction chamber (2).

Abstract: Display apparatus (50) comprising a front projection screen (60), at least one projector (54) which is for providing a display on the screen (60) and which is positioned outside an enclosed display volume, the screen (60) being optimised to preferentially set the image distance in different regions when viewed by an observer (58) via a collimating mirror (62).